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The temp_disable did get rid of the TEMP table
creation step in the star_transformation plan, but
tkprof still shows a very high BUFFER SORT, and the
query failed w/ 'snapshot too old' after 3 Hrs. With
the temp table step, it did finish in 2 1/2 hrs or so.
105 BITMAP MERGE 352207 BITMAP KEY ITERATION 128553935 BUFFER SORT 1627265 TABLE ACCESS BY GLOBAL INDEX ROWID OBJ#(1433369) PARTITION: ROW LOCATION ROW LOCATION 1627265 INDEX RANGE SCAN OBJ#(1433605) (object id 1433605) 352207 BITMAP INDEX RANGE SCANOBJ#(3441108) PARTITION: 1 177 (object id 3441108)
> Hi
>
>
>
> > Rows Operation
> > =========
> =======================================
> >a) 105 BITMAP MERGE
> >b) 351549 BITMAP KEY ITERATION
> >c) 127009880 BUFFER SORT
> >d) 1607720 TABLE ACCESS FULL
> SYS_TEMP_4254956840
> >e) 351549 BITMAP INDEX RANGE SCAN
> OBJ#(3441108)
>
>
>
> I'm not able to explain you what the BUFFER SORT
> exactly does in this case (it should only get the
> data from the temporary table and prepare them for
> the "join" with the index on the fact table...
> Anyway, each time I have a problem with a star
> transformation with temporary tables I try to
> disable the temporary tables (they were/are buggy!).
> Therefore try
> star_transformation_enabled=temp_disable.
>
>
>
>
>
> Regards,
>
> Chris
>
>
>
>
-- http://www.freelists.org/webpage/oracle-lReceived on Mon Aug 08 2005 - 14:45:41 CDT